Apparatus for pneumatically conveying fibrous material



y 23, 96 F. REITERER 3,321,251

APPARATUS FOR PNEUMATICALLY CONVEYING FIBROUS MATERIAL INVENTOR. FEEbINANb REITERER BYMJEZJD%KIMM Q ATTORNEYS F. REITERER May 23, 1967 APPARATUS FOR PNEUMATICALLY CONVEYING FIBROUS MATERIAL Filed June 11, 1964 r 4 Sheets-Sheet 2 ZNVENTOR. FERDINANb Rem-E1222 ATTORNEYS May 23, 1967 F. REITERER 3,321,251

APPARATUS FOR PNEUMATICALLY CONVEYING FIBROUS MATERIAL Filed June ll, 1964 4 Sheets-Sheet 3 in 20' I9 INVENTOR: FERDINAND REWER -R ATTORNEYS May 23, 1967 F. REITERER APPARATUS FOR PNEUMATICALLY CONVEYING FIBROUS MATERIAL Filed June 11, 1964 4 Sheets-Sheet 4 INVENTOR: FEENNANB REWERER ATTORNEYS United States Patent 3,321,251 APPARATUS FOR PNEUMATICALLY CONVEYING FIBROUS MATERIAL Ferdinand Reiterer, Rueil-Malmaison, France, assignor, by direct and mesne assignments, to Etablissements Neu, Lille, France, a French company Filed June 11, 1964, Ser. No. 374,415 Claims priority, application France, June 11, 1963, 937,673 11 Claims. (Cl. 30223) The present invention relates to installations for the pneumatic transportation or conveyance of materials such as fibrous material by means of a so-called blower conveyor device.

Such devices are particularly, though not exclusively, utilized in the textile industry for the transfer of fibers from one machine to another.

Such installations may operate either by blowing, by suction or by combined suction and blowing action.

The choice of mode of operation is determined, on the one hand, by the characteristics of the fibrous material to be transported or conveyed, that is, the length of the fibers, their degree of opening, and their content in dust or impurities, and, on the other, by the length of the conveyor circuit as well as by the distribution of the discharge points.

In practice, the installation operating by suction and blowing action are the most widely used by reason of the simplicity thereof and the relatively low cost of installation thereof.

In installations of this type, the material to be trans ported is sucked across a centrifugal conveyor blower which delivers the same within a duct toward a determined discharge point.

Unfortunately, the passage of the material across the wheel or impeller of the centrifugal blower causes the torsion or twisting of the fibers which constitutes a particularly grave defect and deficiency in the case in which fibrous material to be transported is strongly disentangled. It then happens in effect frequently that these fibers form on the wheel of the blower veritable cords which completely pack the ventilator to the point of blocking the same, and thus cause the stoppage of the entire chain of manufacture.

This twisting of the material is due to the mode of operation of centrifugal blowers which will be briefly recalled hereinafter in order to render more explicit that which will be explained.

A centrifugal blower is constituted by a wheel with blades, or an air impeller, turning within a spiroidal envelope called a volute. The volute comprises a suction inlet disposed along the axis of the wheel, and a discharge or delivery aperture disposed tangentially along the periphery of the volute.

Under the action of the centrifugal force generated by the rotation of the impeller, the air taken along between the blades of the latter is rejected toward the periphery where it is collected by the volute which channels the same to the delivery orifice. The kinetic energy of this air is thus partially transformed into pressure at the output of the impeller.

The expulsion of the air at the periphery of the impeller produces in the suction inlet a depression causing the aspiration of a quantity of air equal to the quantity of air delivered.

A continuous output is thus established, and the d iference of pressure between the output and the input of the blower is the sum of the depression at the suction inlet and the pressure at the delivery orifice which represents the total manometric height supplied by the blower.

It can be seen that in such known devices the air enters axially into the blower and thereupon its direction is changed or deviated by in the blades, and it is delivered radially.

However, since the material to be transported follows rigorously the movements of the air which constitutes its support, it is subjected also to this change in direction of 90, which causes shocks and eddys or swirls which in turn have for effect to wind and twist the transported or conveyed fibrous material which thus forms bundles or packets very difiicult to disentangle.

The conveyor blower according to the present invention, which is not subject to these inconveniences, is characterized essentially by the fact that it comprises a fiber admitting suction inlet oriented tangentially or radially of the Wheel or impeller of the blower.

Optionally, a pair of feed cylinders is disposed between the fiber admitting suction inlet and the periphery of the impeller, and also optionally a rotary condenser is disposed between the fiber admitting suction inlet and the feed cylinders, and still optionally a recuperation box with filter is interposed between the suction inlet and the condenser.

According to another characteristic of the conveyor blower according to the present invention, the latter comprises a perforated ring or drum, provided with projecting portions, points or teeth connecting by means of the same the extremities of the blades of the blower impeller. This arrangement produces a disentangling and carding action of the fibers, and the air entrained between the blades of the impeller and rejected across the perforations of the toothd surface, makes impossible the packing or stufling of the said surface.

The intensity of the disentangling or carding action may be regulated by the modification of the speed of rotation of the impeller and/or, in the case in which the installation comprises feed cylinders, by the adjustment of the speed of rotation of the latter.

The installation according to the present invention may also comprise grids disposed at the output of the volute. These grids permit recuperation of large impurities separated from the fibers by the opening action exerted on these fibers by the toothed wheel of the blower.

Moreover, the volute may comprise points along its internal wall. The length and the density of these points depend on the material to be transported or conveyed; they intensify the tearing and shredding action exercised by the feed cylinders on the waste materials such as rags, cords, etc.

Accordingly, it is an object of the present invention to provide a conveyor blower structure of the type described above which obviates the aforementioned shortcomings and drawbacks encountered with the prior art constructions.

It is another object of the present invention to provide a conveyor blower, especially for textile installations for the conveyance of fibrous materials, which eliminates the twisting of fibers within the centrifugal blower.

Another object of the present invention resides in the provision of a conveyor blower, especially for fibrous materials which is so constructed and arranged as to assure continued proper operation without danger of becoming packed and/or stuffed by cord-like assemblies of the fibrous material that may ultimately cause stoppage of the blower.

Still another object of the present invention resides in the provision of a conveyor blower of the type described above in which winding and twisting of the fibrous materials passing through the blower is avoided by eliminating any sudden changes in the direction of movement of the fibrous materials.

These and other objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the' '3 accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention, and wherein FIGURE 1a is a schematic cross-sectional view of a first embodiment of a conveyor blower in accordance with the present invention in its simplest form;

FIGURE 1b is a sectional plan view taken along line 1b1b in FIGURE 1a;

FIGURE 2a is a longitudinal cross-sectional view through a second or modified embodiment of a conveyor blower in accordance with the present invention;

FIGURE 2b is a partial cross-sectional view taken along line 2b2b of FIGURE 2a;

FIGURE 3 is a sectional plan view of the conveyor blower of FIGURE 2a, and being taken along line 3-3 thereof; and

FIGURE 4 is a sectional plan view, similar to FIG- URE 3, of a third still further modified embodiment of a conveyor blower in accordance with the present invention.

Refer-ring now to the drawings wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIGURES 1a and lb, the installation illustrated therein schematically represents the present invention in its simplest form without feed cylinders and condenser. In these figures, reference numeral 1 designates the fiber admitting inlet or suction mouth of a housing forming a volute 5 for the centrifugal blower, reference numeral 5' designates the delivery outlet and conduit or duct of volute 5, reference numeral 2 the wheel or air impeller of the blower with its circularly arranged spaced blades 2, reference numeral 2" the motor which drives the impeller 2, reference numeral 3 the perforated ring or drum surrounding the impeller 2, and reference numeral 4 the outwardly projecting teeth or points of the ring 3. The ring 3 and teeth 4 constitute a toothed peripheral surface on impeller 2.

The fibrous material, coming from any known machine (not illustrated) falls in the form of flocks into the mouth 1 where it is entrained toward and tangentially of the toothed surface 3, 4 of the impeller by a suction effect caused by the induction due to the high rotational velocity of the impeller and the internal cross section of the volute 5. It should be noted that the rotary air impeller 2 is disposed within and surrounded by volute 5, and is arranged to draw air into volute 5 axially of the impeller and to direct air centrifugally therefrom into the surrounding volute.

The fibrous material thus comes in contact with the points 4 of the perforated ring 3 which seize the material and project the same into the delivery conduit 5' from which it is blown toward a suitable discharge point (not illustrated) Since the flocks of fibers fall into the material inlet 1 in small quantities and with low velocity, the contact thereof with the toothed surface 3, 4 of the impeller, of which the peripheral velocity is very high, has for effect to disentangle very strongly these flocks; this facilitates, of course, the opening work of the fibers carried out by the machines disposed to the rear or downstream of the blower.

In the second embodiment of FIGURES 2a, 2b and 3, reference numeral 6 designates an input conduit for the material, reference numeral 7 a rotating cylindrical condenser of perforated sheet metal, reference numeral 8 an arcuate deflector disposed on the inside of and spaced from the condenser 7 to delimit the suction surface, reference numerals 9 and 9' two feed cylinders, reference numeral 10 a grid of semi-circular shape constituted by flat iron bars 10, reference numeral 1 1 a recuperation box for the impurities, and reference numeral 12 a portion of the delivery duct.

In FIGURE 3 reference numeral 5a designates a volute, reference numeral 13 designates the driving motor of the impeller 2, and reference numeral 14 designates a reduction means controlling the rotation of the assembly consisting of feed cylinders 9, 9' and condenser 7, by the intermediary of meshing pinions 15, 16, 17 and 18. The connecting duct between the suction inlet for impeller 2 and the deflector 8 within condenser 7 is designated by reference numeral 19 and reference numeral 20 designates an air inlet shutter disposed in an auxiliary input orifice 20', while reference numeral 21 designates a screen for filtering the air sucked through the auxiliary air orifice 20. Elements 2, 2', 3 and 4 may be identical in all three embodiments of the invention. It will be observed in FIGURES 2a and 3 that condenser 7 and deflector 8 are located within the enlarged housing 7 which is an extension to the lower portion of input conduit 6. Feed cylinders 9, 9 are located in a restricted passage or fiber admitting suction inlet between housing 7 and volute 5a and are also located between and in close proximity to the periphery of condenser 7 and the toothed surface 3, 4. Additionally, the upper portion of arcuate deflector '8 is provided with a suction air inlet opening 8" (FIG- URE 20).

It is thus seen that the sucked-in material in the input conduit 6 (FIGURE 2) is assembled in sheet form along the periphery of the condenser 7. The surface delimited by the deflector 8 is placed under depression by the duct 19 which connects the suction inlet of the blower with the condenser 7.

The motor 13 onto Whose arbor is fixed the impeller 2 (FIGURE 3) of the blower assures by the intermediary of the reduction means 14 and the pinions 15, 16, 17 and 18, the driving of the feed cylinders 9 and 9 and of the condenser 7.

The condenser 7 brings the material in front of the feed cylinders 9 and 9' which detach the sheet of fibers, and introduce the same tangentially along the periphery, provided with projecting portions, of the impeller 2.

The high rotational speed of the toothed surface 3, 4 of FIGURE 2a also produces a suction effect between feed cylinders 9, 9 to assist in detaching the sheet of fibers from condenser 7. During this operation, the sheet, maintained by the feed cylinders 9 and 9', is subjected to a very efficient disentangling and cleaning action, and thereupon is projected into the delivery duct 12. The internal wall of volute 5a also may be provided with points 4' therealong to intensify the tearing and shredding action on the mass of the fibers as when in rag or cord form, for example.

To recuperate the impurities heavier than the fibers such as seeds, gravel, etc., that is, the waste materials which are not maintained in suspension by the air current, the output of the volute 5a is equipped, over a certain length thereof, with the grid 10 between the bars 10' of which the impurities fall into recuperation box 11.

FIGURE 4 is a plan view of an installation identical to that of FIGURE 3 but comprising additionally a filter box 24 interposed between the condenser 7 and the suction inlet of the blower.

If the material to be conveyed contains a large amount of dust and impurities, it is advantageous to interpose between the blower and the condenser a filtering box 24, connectedto the condenser by a preferably flexible conduit 23 and to the suction inlet of the blower by a flexible conduit 22. Flexible conduits 22, 23 and filter box 24 of FIGURE 4 are used in place of connecting duct '19 of FIGURE 3. Filter box 24 comprises a filter 25 to retain the waste materials, as well as a door 26 to permit the evacuation and removal of the waste.

A suction aperture 20 of which the cross section may be adjusted by a shutter 20 (FIGURE 4) assures an admission of auxiliary air in order to compensate for the small suction cross section of the condenser and to avoid thus a reduction of the output of the blower. Since all elements of the embodiment of FIGURE 4 which have not been specifically described in connection with FIG- URE 4 may be identical to corresponding elements shown in FIGURE 3, such identical elements bear the same reference numerals in both FIGURES 3 and 4 to avoid repetitive description thereof.

While I have shown and described sevenal embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art; and I, therefore, do not Wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

I claim:

1. Apparatus for pneumatically conveying fibrous material without abruptly changing the direction of fiow of the material comprising a centrifugal blower including housing means forming a volute and a rotary air impeller Within and surrounded by said volute and arranged to draw air into said volute axially of said impeller and to direct air centrifugally therefrom into the surrounding volute, said impeller comprising a plurality of circularly arranged spaced blades and a perforated drum encircling and rotatable with said blades, said volute having a material inlet closely adjacent the periphery of said impeller and adapted for the feeding of fibrous material into said volute toward the periphery of said drum, and said volute having a delivery outlet duct spaced from said material inlet and through which the material is conveyed by the air being centrifugally directed into said volute by said impeller whereby the material is conveyed in the volute from the material inlet to the outlet under the impetus of air currents Without abrupt changes in the direction of flow of the material to minimize entanglement of the fibrous material.

2. Apparatus according to claim 1, wherein said air impeller also includes a plurality of points projecting outwardly from said drum for disentangling fibers of the material drawn through said material inlet.

3. Apparatus according to claim 2, including a pair of rotary feed cylinders adjacent said material inlet and the periphery of said air impeller, said cylinders being arranged to assist in directing fibrous material from said material inlet to said impeller.

4. Apparatus according to claim 2, including a plurality of additional points arranged along the internal wall of said volute.

5. Apparatus according to claim 2, including grid means in said delivery outlet duct and so positioned as to entrap heavy particles while permitting lighter fibers to flow thereby.

6. Apparatus according to claim 2, including a rotary cylindrical perforate condenser positioned adjacent said material inlet and exteriorly of said volute for receiving fibrous material against the periphery thereof and from which the material is drawn by suction induced in said material inlet by rotation of said impeller.

7. Apparatus according to claim 6, including a pair of rotary feed cylinders located between said condenser and said impeller and arranged to assist in directing fibrous material from said condenser to said impeller.

8. Apparatus according to claim 7, including means producing suction within said condenser to augment the collection of fibrous material against the periphery thereof, and a stationary deflector within said condenser and corresponding to a portion of the periphery of the condenser adjacent said material inlet such that the suction within said condenser is ineffective to hold fibrous material against the periphery of said condenser adjacent said feed cylinders.

9. Apparatus according to claim 8, in which said means producing suction within said condenser comprises duct means communicatively connecting the interior of said condenser to an air inlet opening through which air is drawn axially of said impeller.

10. Apparatus according to claim 9, including filter means in said duct means and through which air drawn into said condenser flows in its course to said air inlet opening, said duct means serving as a recuperation box between said condenser and said filter means.

11. Apparatus according to claim 9, wherein said duct means is provided with an auxiliary air inlet orifice through which air flows also to said air inlet opening, and means for adjustably varying the size of said auxiliary air inlet orifice.

References Cited by the Examiner UNITED STATES PATENTS 1,203,841 11/1916 Bancel 302-37 1,431,780 10/ 1922 Daign-ault 30237 1,544,407 6/ 1925 Jefiers 30237 1,806,494 5/193 1 OBrien 30237 2,532,330 12/ 1950 Ramsdell 19-156 FOREIGN PATENTS 435,967 10/1926 Germany.

699,761 11/ 1940 Germany. 1,116,153 10/1961 Germany.

760,999 11/ 1956 Great Britain.

ANDRES H. NIELSEN, Primary Examiner.

EVON C. BLUNK, Examiner. 

1. APPARATUS FOR PNEUMATICALLY CONVEYING FIBROUS MATERIAL WITHOUT ABRUPTLY CHANGING THE DIRECTION OF FLOW OF THE MATERIAL COMPRISING A CENTRIFUGAL BLOWER INCLUDING HOUSING MEANS FORMING A VOLUTE AND A ROTARY AIR IMPELLER WITHIN AND SURROUNDED BY SAID V OLUTE AND ARRANGED TO DRAW AIR INTO SAID VOLUTE AXIALLY OF SAID IMPELLER AND TO DIRECT AIR CENTRIFUGALLY THEREFROM INTO THE SURROUNDING VOLUTE, SAID IMPELLER COMPRISING A PLURALITY OF CIRCULARLY ARRANGED SPACED BLADES AND A PERFORATED DRUM ENCIRCLING AND ROTATABLE WITH SAID BLADES, SAID VOLUTE HAVING A MATERIAL INLET CLOSELY ADJACENT THE PERIPHERY OF SAID IMPELLER AND ADAPTED FOR THE FEEDING OF FIBROUS MATERIAL INTO SAID VOLUTE TOWARD THE PERIPHERY OF SAID DRUM, AND SAID VOLUTE HAVING A DELIVERY OUTLET DUCT SPACED FROM SAID MATERIAL INLET AND THROUGH WHICH THE MATERIAL IS CONVEYED BY THE AIR BEING CENTRIFUGALLY DIRECTED INTO SAID VOLUTE BY SAID IMPELLER WHEREBY THE MATERIAL IS CONVEYED IN THE VOLUTE FROM THE MATERIAL INLET TO THE OUTLET UNDER THE IMPETUS OF AIR CURRENTS WITHOUT ABRUPT CHANGES IN THE DIRECTION OF FLOW OF THE MATERIAL TO MINIMIZE ENTANGLEMENT OF THE FIBROUS MATERIAL. 